docs: def get_return_type_indexes(self, data):
          """Get from a docstring the return parameter type indexes.
          In javadoc style it is after @rtype.
  
          :param data: string to parse
          :returns: start and end indexes of found element else (-1, -1)
            Note: the end index is the index after the last included character or -1 if
            reached the end
          :rtype: tuple
  
          """
          start, end = -1, -1
          stl_rtype = self.opt['rtype'][self.style['in']]['name']
          if self.style['in'] in self.tagstyles + ['unknown']:
              dstart, dend = self.get_return_description_indexes(data)
              # search the start
              if dstart >= 0 and dend > 0:
                  idx = self.get_elem_index(data[dend:])
                  if idx >= 0 and data[dend + idx:].startswith(stl_rtype):
                      idx = dend + idx + len(stl_rtype)
                      m = re.match(r'\W*(\w+)', data[idx:])
                      if m:
                          first = m.group(1)
                          start = data[idx:].find(first) + idx
              # search the end
              idx = self.get_elem_index(data[start:])
              if idx > 0:
                  end = idx + start
  
          if self.style['in'] in ['params', 'unknown'] and (start, end) == (-1, -1):
              # TODO: manage this
              pass
  
          return start, end